Field of the Invention
The invention relates to flush valves for toilets, urinals and the like, and more particularly to a modification to the design of such valves to provide a scoop or cover to be placed over the opening to an overflow tube or to a vent tube within the flush valve to help to divert water that may block an overflow tube and facilitate escape of air that may be otherwise trapped within the valve body, the valve throat and/or the toilet manifold.
Description of Related Art
Toilets and toilet assemblies for removing solid and liquid human waste are well known. Typically, toilets incorporate three systems that work together to perform the flushing action: (1) internal water channels of the toilet bowl, (2) the flush mechanism, and (3) the refill mechanism. Working in concert, these three systems enable the flushing function of the toilet.
Usually, a toilet tank, positioned over the back of the toilet bowl in a two-piece toilet assembly or in the upper part of a one-piece assembly with a tank portion, holds water that is used to both initiate flushing of waste from the toilet bowl, through a trapway and into a sewage drain line, and refill the bowl with fresh water. When a user wants to flush the toilet, the user pushes down on a flush lever or other flush actuator on the outside of the tank, which is connected on the inside of the tank typically to a movable chain and/or lever or mechanical flush valve actuator. When the flush lever is depressed on the outside of the tank, the chain or lever on the inside of the tank acts to lift and open a flush valve, enabling water to flow from the tank into the bowl to initiate a toilet flush cycle. In some toilet designs the toilet bowl does not have a tank on the rear portion of the tank, but instead may have an in-line flush valve mounted in a casing on the rear portion of the toilet and in communication with an incoming source of water.
In many toilet designs, water flows from a flush valve directly into the bowl inlet, and is then dispersed into a rim channel, a jet channel(s), an opening and/or directly into the toilet bowl through a manifold area located beneath the toilet bowl inlet. The water releases from the valve into the bowl through the toilet bowl inlet rather quickly, with flow from the flush valve entering the bowl typically lasting only approximately on half to four seconds. The water flows into the bowl either directly, from the rim channel and/or down a jet channel(s) within the bowl which introduces water into the bottom of the toilet bowl through a siphon jet outlet. The siphon jet releases most of the water into the trapway, which initiates siphon action. The siphoning action draws all the water and waste out the bowl, and into the trapway. The waste and water continues through the other end of a generally U-shaped trapway and is released into the wastewater or sewage drain line connected at the base of the toilet.
Once the tank is emptied during the flush, the flush valve closes, and a floating mechanism(s) or other similar tripping device, depending on the flush valve and tank design, initiates opening of a filler valve in a toilet design having fillable tank. A filler valve provides fresh water to both the tank and the bowl through separate flows. Eventually, the tank fills with water to a level high enough to cause the float to rise, thus shutting off the fill valve. At this point, the flushing cycle is complete.
Government agencies have continually demanded that water use for flushing be reduced. Much of the focus in recent years has been to reduce the water demand required by toilet flushing operations. In order to illustrate this point, the amount of water used in a toilet for each flush has gradually been reduced by governmental agencies from 7 gallons/flush (prior to the 1950's), to 5.5 gallons/flush (by the end of the 1960's), to 3.5 gallons/flush (in the 1980's). The National Energy Policy Act of 1995 mandates that toilets sold in the United States can use water in an amount of 1.6 gallons/flush (6 liters/flush) or less.
One attempt in the art to produce a more reliable, more efficient and more powerful 1.6 gallon (6 liter) gravity flush toilet, known as a “high-performance toilet” (HPT), while overcoming the drawbacks in existing toilet technology by increasing the hydraulic energy available during the flushing operation, can be found in U.S. Pat. No. 6,901,610 entitled, “High Performance Valve Assembly For Toilets”; U.S. Pat. No. 6,728,975 entitled, “High Performance Flush Valve Assembly”; and U.S. Pat. No. 6,715,162 for “Toilet Assembly,” commonly owned with the present application. Relevant portions of these patents to the extent they describe radiused inlet technology, general toilet tank operation and construction, and flush valve construction are incorporated herein by reference.
Hush valve assemblies for water tanks of toilets are described in U.S. Pat. Nos. 6,901,601, 6,723,975 and 6,715,162. These patents describe a flush valve having a valve body with a base sleeve portion including a radiused inlet to increase the discharge coefficient of the valve opening. A flush cover member is coaxially and slidably mounted with respect to the valve body so that the valve opening is created therebetween when the flush cover member is removed from the valve body via reciprocating motion. The flush cover member is slidably movable between a first position, wherein the flush cover member is seated on the base sleeve portion of the valve body and thereby obstructs water flow through the valve opening, and a second position, wherein the second valve member is removed from the base sleeve portion of the valve body to permit water flow through the valve opening. A sealing member is provided to ensure a proper seal when the flush cover member is in the first position, and a guiding means is provided that properly aligns and guides the flush valve cover relative to the valve body. The flush valve assembly also includes a trip release mechanism that releases the effects of the flush lever on the flush cover member when the flush cover member reaches its second position, thereby returning the flush cover member to its first rest position prior to the flush lever returning to its own corresponding rest position. In this configuration, the disclosed flush valve assembly ensures compliance with the mandated water requirements and simultaneously provides enhanced cleanliness and waste removal capabilities. The flush valve assembly achieves these functions and also releases the effect of the flush lever so that the valve opening can close before the expiration of a regulatory minimum “hold down” time (1 second without exceeding the total water per flush mandate of 1.6 gallons (6 liters)).
Alternative technologies proposed for providing adequate flush valve efficiency for high-performance toilets may be found in U.S. Pat. No. 7,676,858, which proposes use of a flush valve that has a valve body with a valve seat that defines a flow passage having a portion of its interior flow profile that narrows in a non-linear manner away from the valve seat such that the inner surface of the valve seat in the non-linear portion can be defined by a polynomial expression, i.e., the valve body has a non-linearly curved inner surface.
U.S. Pat. No. 8,079,095, owned by the present applicant, discloses a flush valve that accomplishes water conservation and flush efficiency, as well as the performance goals noted above, by providing a more efficient combination of a radiused inlet and an optional elevated valve body. The flush valve assembly disclosed therein may also have a “poppet” or centrally aligned and guided buoyant float cover for the valve body. This particular design is highly effective if an upwardly buoyant and centrally guided flush cover is used, because the upward lifting of such a cover provides for water intake into the valve opening in 360° configuration. That is, when the buoyant cover lifts, it allows for water to flow in from all directions into the valve opening for supplying water from the toilet tank to the toilet bowl.
As some problems are still encountered when using elevated valve bodies having an optimal radiused inlet designed to enhance flow and maximize hydraulic energy through the valve body with a standard flapper-type valve cover, other improvements have also been made in the art. Flush valve body assemblies having a radiused inlet and elevated valve body, used with the above-noted, poppet, centrally-guided flush cover, are able to handle the increased efficiency and maximized flow through the valve body at reduced volumes of water so as to be useful as high-performance flush valves working with HPT toilets having toilet bowl designs and flush pathways that achieve the 1.6 gallons/flush water conservation standards, some of which may be qualified as high-efficiency toilets (HET) which provide effective flushing at as low as about 1.28 gallon per flush or even lower.
Using a standard two-inch inlet, the flush volume through a high-efficiency flush valve designed to function with high-efficiency toilets (HETs) is very high, even though the volume in the toilet tank available for flushing is lower than prior art traditional toilets. A traditional flapper valve cover's performance used with such a valve body and a two-inch inlet can be affected in terms of its ability to close when appropriate, sometimes closing prematurely, and in terms of its ability to re-open. This problem can sometimes be exacerbated in a radiused inlet valve body design, because the extension of the inlet opening due to the presence of the radius, which is optimized for high-efficiency flow through the valve body. This can require an even larger sized flapper to cover the opening created by the radius thereby contributing to buoyancy issues affecting opening and closing of the flapper cover. These factors can combine to make it difficult to properly open and close a standard flapper on a valve assembly configured for use in an HPT or, preferably an HET and having an elevated valve body and radiused inlet, even in comparison to standard low profile, non-elevated flush valve bodies having standard flapper-type valve covers.
Other issues encountered in flush valve designs arise when such flush valves, whether suitable for high-efficiency toilets or not, are optimized for flow design, but have outlets which, when installed introduce fluid flow directly into an inlet chamber of a toilet bowl having a lower floor which lies in up/one perpendicular to the flow coming out of the flush valve outlet. The impact of the contact between the high flow rate through the valve caused by flushing against the floor of the inlet chamber of the toilet bowl introduces undesirable turbulence which reduces the hydraulic energy available from the water exiting the outlet of the flush valve. Prior art designs are available from the owner of the present application in which a fitting is used on the bottom of a flush valve outlet to divide and direct the flush valve outlet flow into two separate directions so as to introduce flow into the a rim area and into the jet area of the toilet bowl. Such designs do avoid some of the impact issue, for certain particular high-efficiency toilet designs.
Improvements in such designs are described in U.S. Pat. No. 8,266,733, of the applicant hereto, which discloses a valve having an elevated valve body that includes a wall extending between the upper inlet end and the lower outlet end of the valve body with an interior surface that defines flow path extending generally longitudinally through the valve body with a generally circular transverse cross-section. At least a portion of the wall is downwardly linearly tapered so that there is a decreasing valve body diameter and the tapered wall portion is positioned below the radiused inlet portion. The patent also describes a valve flapper with a bulb configuration more readily adaptable to address the buoyancy issues that arise from the high rate of flow through the valve body.
In a farther improvement, co-pending U.S. Provisional application Ser. No. 14/038,748, incorporated herein by reference, describes improved flush valves including those that may have an elevated valve body, wherein the valves incorporate a flush line that connects a flush actuating device to a flush valve cover. The flush line is for raising and lowering the flush valve cover upon actuation of the assembly. A float is connected to the flush valve cover via a the float line or is positioned along the flush line. The float is sufficiently buoyant so as to be capable of resisting the force of flowing water and keeps the flush valve cover open so as to allow flush water to pass through the valve body before closing the flush valve cover when the valve body is installed on a toilet.
Such improvements flow through flush valves, especially for HPT, and preferably HET toilet assemblies create additional challenges to improve efficiencies in flow to continue to improve valve and toilet flush performance while enabling continued conservation of water use. Flow through many of the above-noted high flow valves, which include elevated valve bodies, linearly or non-linearly tapered designs, poppet designs and/or use radiused inlets, can still have issues in terms of turbulence or high flow of water blocking the entrance to the overflow tube of the valve and/or preventing air from escaping the valve, such as through the overflow or vent tubes in the valve designs. As flow rates through the valve are more laminar and fast, as the valve opens to allow water to rush through the valve body towards the toilet, air from within the system can cause obstruction to the benefit achieved by the incoming flow. If the air can pass easily out of the system, any such impact can be minimized. However, the force of the flow can back up the water into the overflow and/or vent tubes from within the valve body in various designs, a typical exit path for air, thus blocking an easy outlet passage for the trapped air. The less trapped air in the incoming flow the better. As a result, there is a need in the art for a way to reduce any negative impact to air release without negatively compromising the enhanced flow rates and flow dynamics achievable by the above-noted improved high efficiency flush valves.